R - 在新的 dataframe 中：如果单元格匹配同一行的另一列，则

Question

d <- data.frame(B1 = c(1,2,3,4),B2 = c(0,1,2,3))
d$total=rowSums(d)

B1 B2 total
1  0  1
2  1  3
3  2  5
4  3  7

Using the dataframe above, I want to create a new dataframe with the following logic:

Going by rows, if cells (B1:B2) matches d$total, return 1, else 0.

Ideally output to look like:

B1n B2n
1   0
0   0
0   0
0   0

What is the best way to do this in R?

Thank you.

Answer 1

You can compare first 2 columns with total value.

res <- +(d[1:2] == d$total)
res
#     B1 B2
#[1,]  1  0
#[2,]  0  0
#[3,]  0  0
#[4,]  0  0

The result is a matrix, if you want dataframe as output you can do res <- data.frame(res) .

Answer 2

Here is an alternate way to solve this problem. You can use dplyr::transmute which is the opposite of dplyr::mutate which will give you two separate columns. Inside transmute are just conditions.

library(dplyr)

newdf <- d %>% transmute(B1n=ifelse(B1+B2==B1,1,0),B2n=ifelse(B1+B2==B2,1,0))
> newdf
  B1n B2n
1   1   0
2   0   0
3   0   0
4   0   0